1. Field of the Invention
The present specification discloses a technology relating to managing log information of events that have occurred. The “log information of events” is referred to as “event log” hereinbelow. This application discloses teachings whereby special data is bound to an event log, so as to easily find tampering with an event log that is transmitted from an information processing device to a log management apparatus through a network, and teachings of managing an event log to which such special data is bound. This application also discloses teaching whereby event log tampering can be easily found without increasing the communication load on the network, by binding special data to the event log. In this application, an “information processing device” refers to a device that is connected with a network, such as a printer or copier or multifunction device.
2. Description of the Related Art
Whenever an event such as a paper jam or printing occurs in a printer (an example of an information processing device), the detail of the occurred event is preferably stored in the form of an event log. This event log may also contain information associated with the event (e.g. in the case of a printing event, information regarding the number of times of printing or the number of printed sheets may be included).
A technique for managing event logs in individual information processing device has been proposed (e.g., see Japanese Patent Application Publication No. 2002-366461). In this technique, management is effected by encrypting the event log of each event. A technique has also been proposed of managing event logs using a server by transmitting the event log to the server. By employing a server, the event logs of all of the information processing devices connected to a network can be managed collectively. Also, the server can manage a large amount of event logs.
When event log is transmitted to the server from the information processing device through the network, there is a risk that the event log may be read by another party and tampered with while the event log passes through the network. Accordingly, the technique has been proposed of transmitting the event log to the server in encrypted form. Such a technique is disclosed in for example Japanese Patent Application Publication No. 2007-174258 or Japanese Patent Application Publication No. 2001-350652. In the latter Publication, a technique is disclosed of transmitting an event log to a server using an encryption technique called SSL (Secure Sockets Layer).